Summary and Discussion 337 



These hypotheses, natural product of the ignorance of the 

 natives, have sometimes been accepted by European travellers. 

 They served as an easy explanation of this curious fact that the 

 intensity of the symptoms is not regularly proportional to the alti- 

 tude, and that at certain points, sometimes of moderate elevation, 

 almost everyone is sick. It is especially travellers in the Andes 

 who believe in emanations from the ground. Some of them would 

 say, like the peons of Brand: "There is much puna here" (page 36) . 



However, very few admit their credulity clearly; they are satis- 

 fied with saying that there are "accompanying causes, which are 

 unknown, and which act with the rarefaction of the air" (page 55) ; 

 that "the atmospheric pressure is not included in the causes of the 

 soroche, which should perhaps be attributed to emanations from 

 the ground" (page 58) . 



Asiatic travellers have been more prudent. Hodgson alone 

 allows one to glimpse a certain credulity (page 223) ; but all the 

 others refuse to admit intoxication by plants; those who have 

 deigned to take note of it declare formally that frequently the 

 symptoms appear where there is no vegetation, not even moss: 

 from Fraser to Mistress Hervey and Drew, they all agree on this 

 point. 



To tell the truth, these hypotheses do not need any other refu- 

 tation. Moreover, the identity of the morbid symptoms attributed 

 now to antimony, now to vapors from the earth, elsewhere to 

 emanations from undetermined plants, is enough to show that 

 they have a single cause, which is closely connected with the ele- 

 vation above sea level. 



Electricity. When. people do not know what else to say, they 

 are very likely to invoke electricity as the cause. Dr. Govan did 

 this (page 221) : "These phenomena," he says, "depend upon atmos- 

 pheric circumstances, less general than the decrease in pressure, 

 like the electric power which must be in a state of constant fluct- 

 uation in the presence of such lofty conductors." For Heusinger 

 (page 245) , electricity must act, for it is stronger and less often 

 negative. But these authors were outdone by Dr. Cunningham, 

 who declared that "in the northern hemisphere, the electricity 

 attracts the blood to the head, and in the southern hemisphere, to 

 the feet .... from which mountain sickness results, which explains 

 why this illness is cured by the horizontal position" (page 225) . The 

 strangest thing is that this strange doctrine has found votaries 

 (page 296) . 



Lack of oxygen in the air. It is the unevenness of the effect of 

 the altitude, according to the regions, which has suggested all these 



